Files
go2rtc/pkg/expr/expr.go
2025-04-22 16:37:10 +03:00

123 lines
2.4 KiB
Go

package expr
import (
"encoding/json"
"fmt"
"io"
"net/http"
"regexp"
"strings"
"github.com/AlexxIT/go2rtc/pkg/tcp"
"github.com/expr-lang/expr"
)
func newRequest(method, url string, headers map[string]any, body string) (*http.Request, error) {
var rd io.Reader
if method == "" {
method = "GET"
}
if body != "" {
rd = strings.NewReader(body)
}
req, err := http.NewRequest(method, url, rd)
if err != nil {
return nil, err
}
for k, v := range headers {
req.Header.Set(k, fmt.Sprintf("%v", v))
}
return req, nil
}
func regExp(params ...any) (*regexp.Regexp, error) {
exp := params[0].(string)
if len(params) >= 2 {
// support:
// i case-insensitive (default false)
// m multi-line mode: ^ and $ match begin/end line (default false)
// s let . match \n (default false)
// https://pkg.go.dev/regexp/syntax
flags := params[1].(string)
exp = "(?" + flags + ")" + exp
}
return regexp.Compile(exp)
}
var Options = []expr.Option{
expr.Function(
"fetch",
func(params ...any) (any, error) {
var req *http.Request
var err error
url := params[0].(string)
if len(params) == 2 {
options := params[1].(map[string]any)
method, _ := options["method"].(string)
headers, _ := options["headers"].(map[string]any)
body, _ := options["body"].(string)
req, err = newRequest(method, url, headers, body)
} else {
req, err = http.NewRequest("GET", url, nil)
}
if err != nil {
return nil, err
}
res, err := tcp.Do(req)
if err != nil {
return nil, err
}
b, _ := io.ReadAll(res.Body)
return map[string]any{
"ok": res.StatusCode < 400,
"status": res.Status,
"text": string(b),
"json": func() (v any) {
_ = json.Unmarshal(b, &v)
return
},
}, nil
},
//new(func(url string) map[string]any),
//new(func(url string, options map[string]any) map[string]any),
),
expr.Function(
"match",
func(params ...any) (any, error) {
re, err := regExp(params[1:]...)
if err != nil {
return nil, err
}
str := params[0].(string)
return re.FindStringSubmatch(str), nil
},
//new(func(str, expr string) []string),
//new(func(str, expr, flags string) []string),
),
expr.Function(
"RegExp",
func(params ...any) (any, error) {
return regExp(params)
},
),
}
func Run(input string) (any, error) {
program, err := expr.Compile(input, Options...)
if err != nil {
return nil, err
}
return expr.Run(program, nil)
}